.20x+.50(12-x)=.30(12)

Solution for .20x+.50(12-x)=.30(12) equation:

Simplifying
0.20x + 0.50(12 + -1x) = 0.30(12)
0.20x + (12 * 0.50 + -1x * 0.50) = 0.30(12)
0.20x + (6 + -0.5x) = 0.30(12)

Reorder the terms:
6 + 0.20x + -0.5x = 0.30(12)

Combine like terms: 0.20x + -0.5x = -0.3x
6 + -0.3x = 0.30(12)

Multiply 0.30 * 12
6 + -0.3x = 3.6

Solving
6 + -0.3x = 3.6

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-6' to each side of the equation.
6 + -6 + -0.3x = 3.6 + -6

Combine like terms: 6 + -6 = 0
0 + -0.3x = 3.6 + -6
-0.3x = 3.6 + -6

Combine like terms: 3.6 + -6 = -2.4
-0.3x = -2.4

Divide each side by '-0.3'.
x = 8

Simplifying
x = 8